This invention is directed to a sacrificial latching system for a pair of intermatable connectors, such as a receptacle and plug as may be used in a cellular phone system, where, through accident or inadvertence, a separation of the respective connectors may be accomplished without destroying the receptacle, for example, within which is found the intricate signal transmission mechanism. The present invention represents a cost-effective way to ensure the integrity of the receptacle by sacrificing the less costly component, the plug, for example.
Conventional connector latching systems, while effective to unmate the respective connectors by a deliberate action of the user, they are not effective where accidental unmating may occur. Such systems typically employ a pair of externally accessible, manually depressible, pivotal members to effect unmating of the connectors. Typically, by manually squeezing such members, the members are laterally moved allowing for the physical separation of the connectors, see U.S. Pat. No. 4,726,783.
U.S. Pat. No. 5,314,347, a more current patent, is another connector latching mechanism that requires operator activation. The mechanism thereof has the disadvantage that the connectors cannot be suitably separated until the operator or user activates the levers of the mechanism. However, there may be situations where separation is desirable without manually activating a latching mechanism. For example, excessive force applied deliberately or by accident, may cause damage or destruction of the connectors' internal mechanism before the latching mechanism is overcome. U.S. Pat. No. 5,199,897 teaches a locking mechanism for connectors, such as a plug and receptacle, that allows separation without manipulating the locking mechanism.
U.S. Pat. No. 5,295,854 teaches a passive latch system for matable connector housings. Each connector housings has at least one working surface depressed from the reference surface thereof to form part of a latching aperture while the other of the housings has at least one working surface raised from the reference surface thereof to form part of a latching projection. The working surface on one of the housings is sloped with respect to its reference surface, and the sloped working surface also is tapered in a direction that is generally parallel with respect to the latching direction.
U.S. Pat. No. 5,011,424, assigned to the assignee hereof, teaches a connector system where pulling on the mated connectors alone disengages one connector from the other. This is achieved by a connector system in which there is a connector having an inner body section and an outer housing section, the inner body section having two latch arms operatively hinged to the connector. The connector has forward of its hinge, a latch arm having latching surfaces at its forward end which latch the connector to a complementary connector. The connector has rearward of the hinge, rotatable actuation arms. The connector is characterized in that the rotatable actuation arms including on the ends, actuator sections having a forwardly directed surface, while the housing includes a rearwardly facing camming surface disposed proximate to the forwardly facing surface, and in that the housing is axially moveable relative to the inner body causing the camming surface to rotate the latch arms about the hinge, thereby unlatching the connector from the complementary connector.
The co-pending application, which for convenience will be discussed with reference to a plug and receptacle as the intermatable electrical connectors secured by the latching system thereof, represents a first approach to providing a latching system that allows inadvertent unmating of connectors without destroying the respective connectors. The system comprises a plug having a pair of flexible arms projecting axially therefrom, where the free ends of the arms include slot means for engaging complementary arms within the receptacle. The receptacle includes a forward ramp surface against which the flexible arms initially ride to effect mating of the plug and receptacle, a rearward surface slightly angled from a base toward the ramp surface, and a metal spring arm mounted within the receptacle in close proximity to the base of the rearward surface. In the mated condition the spring arm engages the slot means, where the angular relationship of the respective engaging arms is 90.degree.. To effect a non deliberate unmating, such as by accident, a maximum predetermined separating force, when applied between the plug and receptacle, causes the spring arm to flex to a position near the rearward surface at a critical release angle to thereby release the free end from its respective spring arm.
The present invention avoids the complexities of the latching mechanisms of the prior art by a simple, yet precise system, that allows for the separation of a pair of mated connectors, at a predetermined level of separating force applied thereto, through the sacrifice of a latching element thereof. The manner by which this is accomplished will become apparent from the further description, particularly when read in conjunction with the accompanying drawings.